And before, when you guys were getting off-topic...you were getting into my "other" hobby...now, i don't want to start another 'off-topic' trend, so if'n y'all go to this link, just enjoy. And remember, this is not regulated by the ATF...this is just 'parts'...No Lower Reciever...lol.

http://www.safetyharborfirearms.com/UltraMag_50/ultramag_50.html

And back on-topic, when moving forward through the water, you will create a wave which will ride up your hood, and maybe windshield, if it gets that deep...hence the reason to suck air from as high as possible. If every important breather on my truck breathes through the snorkel, and my ignition is sealed, i'll keep on truckin, just like the guys in the Heep video earlier.

And judging by the bubbles, thier exhaust was venting underwater, and Thier Heep didnt 'develop maximum backpressure and die'.